Competing reactions of hydrophenylation and phenylation in tetraphenylantimony chloride methyl acrylate palladium chloride system

Article abstract of DOI:10.1134/S1070363206050161

A new catalytic reaction of the competing phenylation and hydrophenylation in air of methyl acrylate with tetraphenylantimony chloride in the presence of PdCl₂ (0.04 mol per 1 mol of organometallic compound) in acetonitrile at 50°C for 6 h was studied. The yields of methyl cynnamate and methyl hydrocynnamate were 0.73 and 0.27 mol mol^-1 respectively. The products ratio obtained depends slightly on the process duration, the Ph ₄SbCl and methyl acrylate ratio, and the structure of Pd salt [PdCl₂, Pd(OAc)₂, Li₂PdCl₄], but significantly on the nature of a solvent (MeCN > DMF > THF). The use of Ph₄SbCl instead of Ph₄SbBr leads to decrease in the yield of methyl hydrocynnamate to 0.04 mol mol^-1. In the reactions of Ph₄SbX (X = F, I, OAc, O₂CEt) the product is not formed at all. Pleiades Publishing, Inc., 2006.

Full text of DOI:10.1134/S1070363206050161

ISSN 1070-3632, Russian Journal of General Chemistry, 2006, Vol. 76, No. 5, pp. 747 752.
Pleiades Publishing, Inc., 2006.
Original Russian Text
No. 5, pp. 784 789.
V.A. Morugova, A.V. Gushchin, G.G. Skvortsov, D.V. Moiseev, 2006, published in Zhurnal Obshchei Khimii, 2006, Vol. 76,
Competing Reactions of Hydrophenylation
and Phenylation in Tetraphenylantimony
Chloride Methyl Acrylate Palladium Chloride System
V. A. Morugova, A. V. Gushchin, G. G. Skvortsov, and D. V. Moiseev
Lobachevskii Nizhnii Novgorod State University, pr. Gagarina 23, Nizhnii Novgorod, 603950 Russia
e-mail: gushchin@mail.nnov.ru
Received September 2, 2005
Abstract A new catalytic reaction of the competing phenylation and hydrophenylation in air of methyl
acrylate with tetraphenylantimony chloride in the presence of PdCl2 (0.04 mol per 1 mol of organometallic
compound) in acetonitrile at 50 C for 6 h was studied. The yields of methyl cynnamate and methyl hydro-
1
cynnamate were 0.73 and 0.27 mol mol respectively. The products ratio obtained depends slightly on the
process duration, the Ph4SbCl and methyl acrylate ratio, and the structure of Pd salt [PdCl2, Pd(OAc)2,
Li2PdCl4], but significantly on the nature of a solvent (MeCN > DMF > THF). The use of Ph4SbCl instead of
1
Ph4SbBr leads to decrease in the yield of methyl hydrocynnamate to 0.04 mol mol . In the reactions of
Ph4SbX (X = F, I, OAc, O2CEt) the product is not formed at all.
DOI: 10.1134/S1070363206050161
Triphenylantimony dicarboxylates Ph3Sb(O2CR)2
are known to act at 50 C in the presence of the
catalytic amounts of Pd(0,II) as a soft C-phenylating
agents for methyl acrylate I. They play the role
simultaneously as a source of phenyl group and as an
oxidant of Pd(0) to Pd(II). The methyl cynnamate II
2-phenylpropanoic and 3-phenylpropanoic acids is
formed [6]. Participation of benzene in the reaction of
hydrophenylation of norbornene and some other non-
activated olefines (2-butene, propylene, cyclopentene,
cyclohexene) has also been studied [7]. This reaction
proceeds in the presence of platinum complexes at the
activation by Ag(I) salt in o-dichlorobenzene benzene
mixture at 80 115 C. The product yield reaches 90%.
Hydrophenylation was also carried out by means of
PhX (X = Br, I, OTf) in Et3N/HCOOH system on the
palladium catalysts in the presence of phosphine
ligands at room temperature. The products yields
reach 50 80%.
1
yield is 1 2 mol mol on the starting organometallic
compound [1]. The phenylating systems on the basis
of Ph3Sb, Ph3SbX2, and Ph4SbX in the presence of
organic peroxides occured to be more effective. The
ester II yield reaches two, and in the case of tetra-
1
phenyl derivatives three mol mol on the starting
organometallic compound [2 4].
Palladium-catalyzed hydophenylation of , -un-
saturated ketones and aldehydes with the trivalent
antimony phenyl derivatives has also been reported
[9]. It was shown that the process takes place in the
presence of stoichiometric amounts of silver acetate.
But with such substrates as methyl acrylate, methyl
cynnamate, styrene, acrylonitrile and allyl acetate the
hydrophenylation product was not found to form.
Reaction does not proceed with another palladium
compounds instead of Pd(OAc)2. That is why the
authors proposed that the role of silver acetate is to
oxidizing of Pd(0) obtained in the course of the
process to Pd(OAc)2.
We have recently found that Ph4SbX as the phe-
nylating agent in the reaction with the ester I in the
absence of peroxides leads besides the product of
phenylation II to the product of hydrophenylation,
methyl hydrocynnamate III. Formation of the latter
was confirmed by chromatomass spectrometry [5].
The process of hydrophenylation presents special
interest for organic synthesis because the simultaneous
hydrogenation and phenylation of unsaturated group
of an organic substrate takes place.
Examples of hydrophenylation of methyl acrylate
and some other alkenes with benzene at the catalysis
with iridium acetylacetonate have been reported. In
that case the reaction proceeds at high temperature
with low selectivity and a mixture of the esters of
The aim of the present work was to study reaction
of hydrophenylation of the ester I with tetraphenyl-
antimony derivatives under mild conditions, to es-
747

748
MORUGOVA et al.
Yields of the products of phenylation and hydrophenyla-
H
H
tion in Ph4SbX I PdCl2 system (1: 3: 0.04 molar ratio) a
H
Ph4SbCl +
Ph
C=C
CO2Me
Yield, mol per 1 mol Ph4SbX
I
Exp. no.
X
H
Ph
H
0.04PdCl2
+
II
III
C=C
H
H
C=C
50 C, MeCN
H
CO2Me
CO2Me
H
II
III
1
2
3
4
5
6
Cl
Br
F
OAc
O2CEt
I
0.73
0.57
0.29
0.21
0.28
0
0.27
0.04
Traces
0
0
0
More thorough investigation of the reaction of
C-phenylation of methyl acrylate with the participation
of Ph4SbCl showed that longer reaction duration does
not cause alteration in the yield and in the products
ratio II:III (see Fig.1). Total yield of the phenylated
1
products was 1 mol mol on Ph4SbCl what tells
a
Reactions were carried out in MeCN at 50 C for 6 h in the
presence of air.
about the participation of one phenyl group only in
the reaction. Besides, from the Fig. 1 is seen that re-
action completes in 6 h. This fact indicates high ac-
tivity of this reagent.
tablish effect of the nature of organometallic com-
pound, palladium catalyst, solvent, and reagent ratio
on the yield of the target product.
For the detailed consideration of the initial stage of
the reaction we investigated the product yield in time
at the smaller concentration of the substrate. The
results obtained showed that the process includes an
induction period. For 3 h the esters III and II res-
pectively were formed in the yield 0.02 and
We studied reaction of a series of tetraphenylanti-
mony derivatives Ph4SbX with the ester I and PdCl2
(1:3:0.04 ratio) in acetonitrile at 50 C. The reaction
was carried out for 6 h. From the table is seen that
tetraphenylantimony chloride exhibits higher activity
both in the reaction of hydrophenylation and in
phenylation of the ester I. The yields of the products
III and II were 0.27 and 0.73 mol mol on the starting
organometallic compound (see the table, exp. 1). In
the case of Ph4SbBr the yield of the ester III sharply
falls to 0.04 mol mol , and the main product was the
1
0.05 mol mol only. The total rate of the process
decreased, but the ratio of the products varied only
slightly in the course of the reaction. Thus, after 6, 12,
18, and 24 h the yield of the ester III was 0.14, 0.24,
0.27, and 0.29 mol mol and of the ester II 0.34,
0.64, 0.66, and 0.70 mol mol , respectively.
1
1
1
1
1
ester II (0.57 mol mol , exp. 2). Tetraphenylanti-
mony fluoride, acetate, and propionate gave the ester
II in low yield only (0.21 0.29 mol mol , exp. 3 5).
Tetraphenylantimony iodide was not reactive at all
(exp. 6).
Dependence the products ratio at hydrophenylation
and phenylation on the ratio of the starting reagents
was also studied. We have previously shown that in
the case of Ph3Sb(OAc)2 decrease in the concentration
of the ester I leads to the sharp decrease in the yield
of the product of phenylation and to formation of the
product of homocombination [10]. In the process
under investigation we found that varying the ratio of
organometallic compound and the ester I from 1:5 to
1:1 leads to the simultaneous decrease in the yield the
1
Thus, Ph4SbCl3 provides the largest yields of the
products of hydrophenylation and phenylation accor-
ding to the following scheme:
1
2
1
product III from 0.29 to 0.10 mol mol and of the
1
compound II from 0.71 to 0.24 mol mol , but their
ratio remains close to 0.4. In all the cases no diphenyl
formation was found. The results obtained are listed in
the Fig. 2.
We found that the yields of the products III and II
slightly depend on the nature of palladium salt, PdCl2,
LiPdCl4 or Pd(OAc)2. For example, in the reaction of
Ph4SbCl with the ester I and the palladium salt
(1:2:0.04) in acetonitrile at 50 C for 6 h the yields
6
12
18
24
Reaction time, h
Fig. 1. Yields of the products (1) II and (2) III in the
reaction of ester I with Ph SbCl (3:1) in the presence of
4 mol% of PdCl (MeCN, 50 C).
4
1
of the esters II and III were 0.34 and 0.14 mol mol
2
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 5 2006

COMPETING REACTIONS OF HYDROPHENYLATION AND PHENYLATION
749
1.0
1.0
1
0.29
0.16
0.84
0.27
2
1
0.8
0.6
0.27
0.66
2
0.8
0.6
0.03
0.13
0.34
0.4
0.2
0
0.4
0.71
1:5
0.7
0.1
0.66
THF
0.2
0
0.27
DMF
MeCN
1:1
1:2
1:3
Ph4SbCl:methylacrylate ratio
Fig. 2. Yields of the products (1) II and (2) III in the
reaction of the ester I with Ph SbCl (4 mol% of PdCl ,
Fig. 3. Yields of compounds (1) II and (2) III in the
reaction of the ester I with Ph SbCl (3:1) in the presence
4
2
4
MeCN, 50 C) depending on the reagent ratio.
of 4 mol% of PdCl at 50 C in different solvents.
2
1
for PdCl2, 0.37 and 0.14 mol mol for Li2PdCl4, and
tion. On the first stage the cross-combination of
Ph4SbCl with the substrate I takes place with the
catalytic participation of palladium salt. Reaction
proceeds according to the equation (1). Evolving
hydrogen chloride adds to the unreacted ester I to
form methyl 3-chloropropanoate. The latter reacts
with Ph4SbCl with the participation of PdCl2 to give
product III and Ph3SbCl2.
1
0.31 and 0.11 mol mol for Pd(OAc)2.
Nature of solvent also plays significant role in the
process under investigation. Besides acetonitrile,
DMF (N-donor) and THF (O-donor) were chosen.
From the Fig.3 is seen that the yield of the ester III
is the largest in acetonitrile (0.27 mol mol ), in DMF
it is close to the same value, but sharply decreases to
1
1
0.03 mol mol at the transfer to THF (O-donor).
Ph4SbCl + CH2=CH COOMe
Contrary to the product III the yields of the ester II
in all the cases remain high (0.66 0.84 mol mol )
[Pd]
(1)
PhCH=CH COOMe + HCl + Ph3Sb.
1
and slightly differ with solvent.
Presence of triphenylantimony in the reaction
products was confirmed by TLC.
It is important to note that the dependence of the
yields of the products on the reaction conditions is
more expressed when tetraphenylantimony rather than
chloride bromide is used. The product III is formed
in small amount in the reaction with the ester I in
acetonitrile in the presence of PdCl2 (1 4 mol%). The
yield of the product II strongly depends on the ca-
For checking above scheme we prepared an authen-
tic sample of methyl 3-chloropropanoate by hydro-
chlorination of the ester I. But heating of Ph4SbCl
with methyl 3-chloropropanoate under the common
conditions (Ph4SbCl:ClCH2CH2COOMe:PdCl2
=
1:3:0.04) gave neither the product II nor the com-
pound III. Alternative scheme of formation of the
product III in the secondary reaction of triphenyl-
antimony with the ester I and HCl evolving on the
stage of primary phenylation according to the follow-
ing equation may be also offered.
1
1
talyst [0.57 mol mol for PdCl2, 0.33 mol mol for
Pd(OAc)2, zero for Pd(dppf)Cl2 and Pd(PPh3)Cl2] as
1
well as on the nature of solvent (0.57 mol mol for
1
1
MeCN, 0.25 mol mol for DMF, 0.07 mol mol for
1
MeOH, 0.06 mol mol for AcOH and THF). In the
last case 0.09 mol mol 1 of diphenyl was also detected.
The above results allow to conclude that the process
of hydrophenylation of the starting ester I as well as
the process of its phenylation is catalytic one. The
Ph3Sb + HCl + CH2=CHCO2Me
[Pd]
(2)
PhCH2CH2CO2Me + Ph2SbCl.
1
yield of the product III reaches 7 mol mol (see the
table, exp. no 1), and of the product II 18 mol mol .
1
The process was carried out under common condi-
tions at the Ph3Sb:I:HCl ratio 1:3:1. Hydrogen
chloride was added to the reaction mixture as a sa-
turated solution in acetonitrile. The expected ester III
was detected in the reaction mixture in the yield
Both processes are connected with one another be-
cause in almost all the experiments the ester II is the
single product or is obtained together with the ester
II. In connection with that we have proposed that the
reaction of hydrophenylation of the starting ester II
is secondary one in relation to the reaction of phenyla-
1
0.005 mol mol only. Hence, though the possibility
of formation of ester III using Ph3Sb was established,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 5 2006

750
MORUGOVA et al.
the above result shows that this process can not be
the main source of compound III due to low yield.
of HCl causes strong decrease in the yields of the
products IIIand II to 0.04 and 0.06 mol mol res-
1
pectively. Hence, shortage of HCl brakes the cycle of
hydrophenylation due to lack of the stage of acydo-
lysis of palladium alkoxide.
We suggest that the processes of phenylation and
hydrophenylation of the ester I proceed in pa-
rallel. The source of phenyl groups in both processes
is the tetraphenyl derivative of antimony(V). In this
case the active form of Pd(0) is oxidized with Ph4SbX
to the phenylpalladium intermediate PhPdX which
simultaneously takes part in two catalytic cycles ac0
cording to the scheme (2). It may add to the ester I
according to the scheme of 1,2- as well as 1,4-addi-
tion. In the first case the catalytic cycle proceeds with
the formation of the ester II and evolution of Ph3Sb
and HCl. Further transformation of Pd(0) to Pd(II)
proceeds via redox transmetallation with Ph4SbCl
which is reduced to triphenylantimony. The inner
cycle of this scheme has been thoroughly considered
by us earlier [4, 5].
PhCH2CH=C(OMe)OPdCl + HCl
[PhCH2CH=C(OMe)OH] + PdCl2.
Excess of HCl suppresses reversible ionization of
the starting Ph4SbCl at Sb Cl bond what leads to
desseleration of transmetallation with palladium
compounds [10], and hence complifies the formation
of PhPdCl occurring in the reactions of phenylation
and hydrophenylation. These facts agree with the
effect of the increase in the rate of hydrophenylation
at the adding of water. In the Ph4SbCl I PdCl2 H2O
system (1:3:0:04:1) under the typical conditions
(MeCN, 50 C, 6 h) the yield of the ester III increases
1
to 0.4 mol mol while the yield of the ester II
1
MeO
OH
remains as high as 0.77 mol mol . Obviously, water
C
can decompose palladium alkoxide similarly to HCl
but it does not suppress the Ph4SbCl ionization.
CH
III
CH2
Ph
PdCl2
Ph4SbCl
Pd(0)
Ph3SbCl2
EXPERIMENTAL
GLC analysid of volatile products was carried out
on a Tsvet-560 chromatograph with the flame ioniza-
tion detector and argon as a carrier gas. For the eva-
luation of methyl hydrocynnamate, methyl cynnamate,
and diphenyl 2400 3 mm column was used filled
with 15% of Apieson L on Chromaton N-AW-DMCS
at 230 C.
MeO
OPdCl
HCl
C
CH
CH2
Ph
HPdCl
Ph3Sb
II
Ph4SbCl, Ph4SbBr, Ph4SbF, Ph4SbI, Ph4SbOAc,
and Ph4ScO2CEt were prepared according to the pro-
cedures [11]. Commercial PdCl2 was used without
further purification. Pd(OAc)2 was prepared by oxida-
tion of palladium black with nitric acid in AcOH for
30 h, yield 80% after crystallization from AcOH [12].
Li2PdCl4 was prepared by dissolution of PdCl2 and
LiCl (1:2) in boiling water, evaporation of water, and
drying of the residue by spraying in a vacuum at
100 C [13]. The ester I was washed with aqueous
alkali solution until the disappearance of yellow co-
loration, dried over sodium sufate, and distilled at
decreased pressure. Methyl 3-chloropropanoate was
prepared according to [14] from the ester I and HCl in
60% yield, bp 155 157 C; n2D0 1.4263. Organic sol-
vents were purified according to the published pro-
cedures [15, 16].
PhPdCl
I
Simultaneous 1,4-addition of PhPdCl to the ester I
forms palladium alkoxide. Acidolysis of the latter
under the action of HCl leads to formation of enol
which immediately rearranges to the stable product
III. This reaction regenerates PdCl2 which then enters
the reaction of transmetallation with Ph4SbCl to form
PhPdCl and Ph3SbCl2.
We established important specific features of par-
ticipation of HCl in the reaction of hydrophenylation
of the ester I. On the one hand, addition of Et3N (1
1
mol mol of organometallic compound) for neutrali-
zation of HCl leads to formation of ester II only in
the yield 0.27 mol mol . No formation of the ester
III under these conditions occurs. On the other hand
increase in the concentration of HCl at adding 1 equiv.
Reaction of Ph4SbCl with the ester (I) in the
presence of 4 mol% of PfCl2. To a mixture of
0.233 g of Ph4SbCl and 3.6 mg of PdCl2 the freshly
prepared solution of 0.135 ml of compound I in 4 ml
1
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 5 2006

COMPETING REACTIONS OF HYDROPHENYLATION AND PHENYLATION
751
of MeCN was added. The ampule was sealed and
thermostated at 50 C for 6 h. The solvent and the un-
reacted ester I were distilled off at reduced pressure.
The solid residue was purified from inorganic pro-
ducts by filtration through a short column filled with
silica gel, elution with 4:1 hexane ether. Obtained
filtrate was analyzed by GLC. Compound II, 59 mg,
and the ester III, 22 mg, were found.
triethylamine, and the ampule was sealed and thermo-
stated at 50 C for 6 h. Analysis of the reaction pro-
ducts was carried out according to the above-presented
procedure. Compound II, 22 mg, was found.
Reaction of Ph4SbCl with methyl 3-chloropropa-
noate. To a mixture of 0.233 g of Ph4SbCl and
3.6 mg of PdCl2 the freshly prepared solution of
0.052 ml of ClCH2CH2COOMe in 4 ml of NeCN was
added. Reaction mixture was degased, the ampule was
sealed, and kept for 6 h at 50 C. After that 55 mg
of diphenyl was found.
Reaction of Ph4SbCl with the ester I in the pre-
sence of another palladium compounds, in another
solvents, and also the reactions of organoantimony
compounds with another acidic residues were carried
out analogously.
ACKNOWLEDGMENTS
Reaction of Ph3Sb with the ester (I) and
4 mol% of PdCl2 in the presence of the equimolar
amount of HCl. To a solution of 0.177 g of Ph3Sb in
2 ml of MeCN 0.25 ml of 2 M HCl solution in aceto-
nitrile was added. Resulting mixture was treated with
a solution of 3.6 mg of PdCl2 and 0.135 ml of com-
pound I in 1.75 ml of MeCN. The ampule was sealed
and heated at 50 C for 6 h. After that the ampule was
opened, the solvent was removed, and the solid re-
sidue was treated similarly to the above-described
procedure. Formation of 0.4 mg of the ester III was
established.
The work was carried out with the support of the
Federal Program Integration of Science and Higher
Education in Russia in 2002 2006 (state contract
no. Z4234/2) and Competing Center of Basic Natural
Sciences of the SPbGU (grant no. A04-2.11-526).
REFERENCES
1. Moiseev, D.V., Gushchin, A.V., Shavirin, A.S., Kur-
sky, Yu.A., and Dodonov, V.A., J. Organometal.
Chem., 2003, vol. 667, nos. 1 2, p. 176.
2. Moiseev, D.V., Morugova, V.A., Gushchin, A.V.,
and Dodonov, V.A., Tetrahedron Lett., 2003, vol. 44,
no. 15, p. 3155.
Reaction of Ph4SbCl with the ester (I) in the
presence of 4 mol% of PdCl2 with the addition of
aqueous HCl solution. To a mixture of 0.233 g of
Ph4SbCl and 3.6 mg of PdCl2 the freshly prepared
solution of 0.135 of the ester I in 4 ml of MeCN was
added. Resulting mixture was treated with 0.04 ml of
11.8 M HCl. The ampule was sealed and thermostated
at 50 C for 6 h. Analysis of the reaction products was
carried out according to the abovementioned proce-
dure. Compound II, 4.5 mg, and 3.5 mg of the ester
III were found.
3. Moiseev, D.V., Gushchin, A.V., Morugova, V.A., and
Dodonov, V.A., Izv. Akad. Nauk, Ser. Khim., 2003,
no. 9, p. 1971.
4. Moiseev, D.V., Morugova, V.A., Gushchin, A.V.,
Shavirin, A.S., Kursky, Yu.A., and Dodonov, V.A.,
J. Organomet. Chem., 2004, vol. 689, no. 4, p. 731.
5. Grunova, E.V., Faerman, V.I., Gushchin, A.V., Shavi-
rin, A.S., Kursky, Yu.A., and Dodonov, V.A., Vestn.
Nizhegorod. Univ. Ser. Khim., 2004, no. 1, p. 20.
Reaction of Ph4SbCl in the presence of 4 mol%
of PdCl2 with the addition of water. To a mixture
of 0.233 g of Ph4SbCl and 3.6 mg of PdCl2 the
freshly prepared solution of 0.135 ml of the ester I in
4 ml of MeCN was added. Resulting mixture was
treated with 9 l of water. The ampule was sealed and
thermostated for 6 h at 50 C. Analysis of the reaction
products was carried out according to above-presented
procedure. Compound II, 63 mg, and 32 mg of the
ester III were found.
6. Matsumoto, T., Periana, R.A., Taube, D.J., and
Yoshida, H., J. Mol. Cat. (A), 2002, vol. 180, nos. 1
2, p. 1.
7. Karshtedt, D., Bell, A.T., and Don Tilley, T., Organo-
metallics, 2004, vol. 23, no. 18, p. 4169.
8. Drago, D. and Pregosin, P.S., Organometallics, 2002,
vol. 24, no. 6, p. 1208.
Reaction of Ph4SbCl with the ester (I) in the
presence of 4 mol % of PdCl2 and the addition of
triethylamine. To a mixture of 0.233 g of Ph3SbCl
and 3.6 mg of PdCl2 the freshly prepared solution of
0.135 ml of the ester I in 4 ml of MeCN was
added. Resulting mixture was treated with 69 l of
9. Cho, C.S., Motofusa, S., Ohe, K., and Uemura, S.,
Bull. Chem. Soc. Jpn, 1996, vol. 69, no. 8, p. 2341.
10. Moiseev, D.V., Cand. Sci. (Chem.) Disseratiotion,
Nizhnii Novgorod, 2003.
11. Gushchin, A.V., Grunova, E.V., Moiseev, D.V., Mo-
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 5 2006

752
MORUGOVA et al.
rozov, O.S., Shavyrin, A.S., and Dodonov, V.A., Izv.
Akad. Nauk, Ser. Khim., 2003, no. 6, p. 1302.
Laboratory Course of Organic Chemistry), Kost, A.N.,
Ed., Moscow: Mir, 1965, p. 505.
15. Waisberger, A., Proskauer, E., Riddik, J., and Tups, E.,
Orgaicheskie rastvoriteli (Organic Solvents), Moscow:
Inostrannaya Literatura, 1958.
12. Stephenson, T.A., Morehouse, S.M., Powell, A.R.,
Heffer, J.P., and Wilkinson, G., J. Chem. Soc., 1965,
vol. 6, no. 6, p. 3632.
16. Bekker, H., Berger, W., and Domshke, G., Organikum.
Praktikum po organicheskoi khimii (Organicum.
Laboratory Course of Organic Chemistry), Moscow:
Mir, 1979, vol. 2. p. 353.
13. Heck R.F., J. Am. Chem. Soc., 1968, vol. 90, no. 20,
p. 5518.
14. Obshchii praktikum po organicheskoi khimii (General
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 5 2006